CVE-2021-36923 : Security Advisory and Response

RtsUpx.sys in Realtek RtsUpx USB Utility Driver for Camera/Hub/Audio through 1.14.0.0 allows local low-privileged users to achieve unauthorized access to USB device privileged IN and OUT instructions via a crafted Device IO Control packet to a device.

Understanding CVE-2021-36923

This CVE identifies a vulnerability in Realtek RtsUpx USB Utility Driver that could lead to various security risks such as Escalation of Privileges, Denial of Service, Code Execution, and Information Disclosure.

What is CVE-2021-36923?

The CVE-2021-36923 vulnerability in Realtek RtsUpx USB Utility Driver allows local low-privileged users to gain unauthorized access to USB devices, potentially leading to severe security consequences.

The Impact of CVE-2021-36923

This vulnerability could result in Escalation of Privileges, Denial of Service, Code Execution, and Information Disclosure, posing significant risks to the security and integrity of affected systems.

Technical Details of CVE-2021-36923

The following provides more insights into the specific technical aspects of CVE-2021-36923:

Vulnerability Description

The vulnerability in RtsUpx.sys enables unauthorized access to USB device privileged instructions through specially crafted Device IO Control packets, allowing malicious actors to exploit this weakness.

Affected Systems and Versions

Realtek RtsUpx USB Utility Driver versions up to and including 1.14.0.0 are affected by this vulnerability, impacting systems that utilize this driver for Camera, Hub, and Audio functions.

Exploitation Mechanism

By sending a specially crafted Device IO Control packet to a USB device, local low-privileged users can exploit this vulnerability to gain unauthorized access to privileged IN and OUT instructions, thereby compromising system security.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-36923, the following steps are recommended:

Immediate Steps to Take

Users are advised to apply security patches provided by Realtek promptly or follow any specific guidance outlined in security advisories to address this vulnerability as soon as possible.

Long-Term Security Practices

Implementing least privilege access policies, regular security updates, and monitoring USB-related activities can help enhance overall system security and reduce the likelihood of exploitation.

Patching and Updates

Regularly check for security updates and patches released by Realtek for the RtsUpx USB Utility Driver to ensure that systems are protected against known vulnerabilities.